--- plugin_2pass1.c	2003/12/17 15:16:16	1.1.2.10
+++ plugin_2pass1.c	2004/01/21 07:14:29	1.1.2.15
@@ -22,16 +22,25 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
- * $Id: plugin_2pass1.c,v 1.1.2.10 2003/12/17 15:16:16 edgomez Exp $
+ * $Id: plugin_2pass1.c,v 1.1.2.15 2004/01/21 07:14:29 syskin Exp $
  *
  *****************************************************************************/
 
 #include <stdio.h>
+#include <errno.h> /* errno var (or function with recent libc) */
+#include <string.h> /* strerror() */
 
 #include "../xvid.h"
 #include "../image/image.h"
 
 
+/* This preprocessor constant controls wheteher or not, first pass is done
+ * using fast ME routines to speed up the 2pass process at the expense of
+ * less precise first pass stats */
+#define FAST1PASS
+#define FAST1PASS_QPEL_TOO
+
+
 /* context struct */
 typedef struct
 {
@@ -63,6 +72,33 @@
 	if((rc->stat_file = fopen(param->filename, "w+b")) == NULL)
 		return(XVID_ERR_FAIL);
 
+	/* I swear xvidcore isn't buggy, but when using mencoder+xvid4 i observe
+	 * this weird bug.
+	 *
+	 * Symptoms: The stats file grows until it's fclosed, but at this moment
+	 *           a large part of the file is filled by 0x00 bytes w/o any
+	 *           reasonable cause. The stats file is then completly unusable
+	 *
+	 * So far, i think i found "the why":
+	 *  - take a MPEG stream containing 2 sequences (concatenate 2 MPEG files
+	 *    together)
+	 *  - Encode this MPEG file
+	 *
+	 * It should trigger the bug
+	 *
+	 * I think this is caused by some kind of race condition on mencoder module
+	 * start/stop.
+	 *  - mencoder encodes the first sequence
+	 *    + xvid4 module opens xvid-twopass.stats and writes stats in it.
+	 *  - mencoder detects the second sequence and initialize a second
+	 *    module and stops the old encoder
+	 *    + new xvid4 module opens a new xvid-twopass.stats, old xvid4
+	 *      module closes it
+	 *
+	 * This is IT, got a racing condition.
+	 * Unbuffered IO, may help ... */
+	setbuf(rc->stat_file, NULL);
+
 	/*
 	 * The File Header
 	 */
@@ -81,8 +117,13 @@
 
 static int rc_2pass1_destroy(rc_2pass1_t * rc, xvid_plg_destroy_t * destroy)
 {
-	fclose(rc->stat_file);
-	free(rc);
+	if (rc->stat_file) {
+		if (fclose(rc->stat_file) == EOF) {
+			DPRINTF(XVID_DEBUG_RC, "Error closing stats file (%s)", strerror(errno));
+		}
+	}
+	rc->stat_file = NULL; /* Just a paranoid reset */
+	free(rc); /* as the container structure is freed anyway */
 	return(0);
 }
 
@@ -91,11 +132,52 @@
 {
 	 if (data->quant <= 0) {
 		if (data->zone && data->zone->mode == XVID_ZONE_QUANT) {
+			/* We disable no options in quant zones, as their implementation is
+			 * based on the fact we do first pass exactly the same way as the
+			 * second one to have exact zone size */
 			rc->fq_error += (double)data->zone->increment / (double)data->zone->base;
 			data->quant = (int)rc->fq_error;
 			rc->fq_error -= data->quant;
 		} else {
 			data->quant = 2;
+
+#ifdef FAST1PASS
+			/* Given the fact our 2pass algorithm is based on very simple
+			 * rules, we can disable some options that are too CPU intensive
+			 * and do not provide the 2nd pass any benefit */
+
+			/* First disable some motion flags */
+			data->motion_flags &= ~XVID_ME_CHROMA_PVOP;
+			data->motion_flags &= ~XVID_ME_CHROMA_BVOP;
+			data->motion_flags &= ~XVID_ME_USESQUARES16;
+			data->motion_flags &= ~XVID_ME_ADVANCEDDIAMOND16;
+			data->motion_flags &= ~XVID_ME_EXTSEARCH16;
+
+			/* And enable fast replacements */
+			data->motion_flags |= XVID_ME_FAST_MODEINTERPOLATE;
+			data->motion_flags |= XVID_ME_SKIP_DELTASEARCH;
+			data->motion_flags |= XVID_ME_FASTREFINE16;
+			data->motion_flags |= XVID_ME_BFRAME_EARLYSTOP;
+
+			/* Now VOP flags (no fast replacements) */
+			data->vop_flags &= ~XVID_VOP_MODEDECISION_RD;
+			data->vop_flags &= ~XVID_VOP_FAST_MODEDECISION_RD;
+			data->vop_flags &= ~XVID_VOP_TRELLISQUANT;
+			data->vop_flags &= ~XVID_VOP_INTER4V;
+			data->vop_flags &= ~XVID_VOP_HQACPRED;
+
+			/* Finnaly VOL flags
+			 *
+			 * NB: Qpel cannot be disable because this option really changes
+			 *     too much the texture data compressibility, and thus the
+			 *     second pass gets confused by too much impredictability
+			 *     of frame sizes, and actually hurts quality */
+#ifdef FAST1PASS_QPEL_TOO
+			/* or maybe we can disable it after all? */
+			data->vol_flags &= ~XVID_VOL_QUARTERPEL;
+#endif
+			data->vol_flags &= ~XVID_VOL_GMC;
+#endif
 		}
 	}
 	 return(0);
@@ -105,9 +187,10 @@
 static int rc_2pass1_after(rc_2pass1_t * rc, xvid_plg_data_t * data)
 {
 	char type;
+	xvid_enc_stats_t *stats = &data->stats;
 
 	/* Frame type in ascii I/P/B */
-	switch(data->type) {
+	switch(stats->type) {
 	case XVID_TYPE_IVOP:
 		type = 'i';
 		break;
@@ -126,13 +209,14 @@
 
 	/* write the resulting statistics */
 
-	fprintf(rc->stat_file, "%c %d %d %d %d %d\n",
-        type,
-		data->quant,
-		data->kblks,
-        data->mblks,
-        data->ublks,
-        data->length);
+	fprintf(rc->stat_file, "%c %d %d %d %d %d %d\n",
+			type,
+			stats->quant,
+			stats->kblks,
+			stats->mblks,
+			stats->ublks,
+			stats->length,
+			stats->hlength);
 
 	return(0);
 }